In vitro permeability measurements showed that the exosome miR-25-3p of NSCLC cells significantly promoted HUVEC permeability and angiogenesis, reduced the levels of KLF2, ZO-1, occludin, Claudin5, and increased VEGF/MMP2/MMP9 level. The gene discussed is VEGFA; the disease is non-small cell lung carcinoma.